<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">

  <input type="text" v-model="n1">
  <input type="text" v-model="n2">
  <input type="button"value="加"@click="f(1)">
  <input type="button"value="减" @click="f(2)">
  <input type="button"value="乘" @click="f(3)">
  <input type="button"value="除" @click="f(4)">
    <hr>
    <h1>结果:{{result}}</h1>
</div>
<script src="js/vue.min.js"></script>
<script>
  let v=new Vue({
    el:"#app",
    data:{
      result:"",
        n1:"",
        n2:""
    },
    methods:{
      f(x){
        if (isNaN(v.n1)||isNaN(v.n2)){
            v.result="输入错误"
            return;
        }
        switch(x){
            case 1:
                v.result = v.n1*1+v.n2*1;
                break;
            case 2:
                v.result = v.n1-v.n2;
                break;
            case 3:
                v.result = v.n1*v.n2;
                break;

            case 4:
                v.result = v.n1/v.n2;
                break;
        }
      }
    }
  })
</script>
</body>
</html>